1. Field of the Invention
This invention relates to a spring retainer for engaging and holding a mat more or less stationary against the inner side of the ribbed front face flange of a rectangular picture frame, which is usually composed of a metal such as aluminum.
2. Description of the Prior Art
The Spertus U.S. Pat. No. 2,651,129 shows an integrated rectangular picture frame, conventionally having a perimetric wall, a ribbed front face flange and a ribbed rear face flange with a mat pressed against the inner side of the front face flange. Both flanges and the interposed perimetric wall of each frame member cooperate to form on each face flange, a U-shaped channel which opens inwardly. A pair of rod-like L-shaped members is provided, one for each of two opposed frame channels. The vertical leg of each ell is placed in its channel and arranged for rotation from one position, wherein said leg and its foot are located wholly within the confines of the frame, to another position, wherein said foot projects outwardly from the frame to support it in an upright position on a horizontal surface. Each leg is retained in its place within its channel and pressed against the mat by a spring retainer interposed between it and the inner side of the rear face flange. This spring comprises an arcuate strip of spring sheet metal having its ends forked to straddle the leg of the L-shaped member and its center dented rearwardly to project into a complementary opening in the rear face flange.
The Tuchinsky et al U.S. Pat. No. 3,613,280 shows a similarly flanged rectangular frame with several spaced spring retainers, each comprising a planar rectangular base arranged in face-to-face contact with the inner face of the perimetric wall and provided with a spring-like flap which extends inwardly and forwardly to press resiliently against a surface interposed between it and the front face flange.
The Chambers U.S. Pat. No. 3,901,496 also shows a similarly flanged rectangular picture frame with a pair of "Spertus type" spring retainers, each comprising a strip of spring sheet metal bent to an arcuate shape with its ends forked and its center barbed. In Chambers, the forked ends straddle a rib of the rear face flange while its barbed center digs into the mat which the spring presses against the ribbed front face flange.